Guest Post by Lindsay Heger and Wendy Wong. In a recent and rare speech, Syrian President Bashar al-Assad dug in his heels. While nobody could have realistically expected him to simply walk away from his post or even give much ground to the opposition, negotiations seemed possible. After all, the rebels had made several recent and promising military advances. In December the Obama administration acknowledged the rebel movement as representative of the Syrian people, increasing pressure on Assad to step down. Even Russian officials, who seemed loyal to a fault, had begun showing signs of...